Brain oscillatory activity evoked by chirp modulated tones in healthy children.

AIM

To describe the features of cortical oscillatory activity and neuronal synchronization by monitoring responses evoked by chirp-modulated tone (CMT) and look for relationships with cognition in healthy children.

METHODS

We recruited 23 healthy children, 1-18 years old, assessed their cognitive abilities and recorded the cortical oscillatory activity evoked by CMTs. We obtained descriptive statistics and looked for correlations with cognitive abilities.

RESULTS

In the low gamma band, the neuronal synchronization evoked by CMTs increased with age, reaching adult features by 12 years of age (rho = 0.5; p = 0.042). In the high gamma band, neuronal recruitment was greater at younger ages (rho = -0.55; p = 0.029). In four of the six under-6-year-old participants, there was no CMT-evoked response. We found that the greater a child's receptive vocabulary skills, the lower the frequency at which maximal neuronal recruitment occurred (rho = -0.65; p = 0.003).

INTERPRETATION

CMT-evoked cortical oscillatory activity is affected by degree of brain maturation and could be a potential biomarker of language-related disability. Our description of the cortical responses evoked by CMTs in healthy children is a step towards recognition of abnormal patterns and the possible use of this approach as a biomarker of brain disorders in children.